While the prime minister is in Manchester, opposition leader Jeremy Corbyn will tour an exhibition of suffragettes in the Museum of London.
To commemorate the 100-year anniversary of women's suffrage in Britain, Amnesty and Newsquest Berkshire are calling upon readers to nominate the incredible women who are working to make a real difference in their local community today.
Relatives of the Suffragettes, as well as leading lawmakers including Ruth Davidson, the Scottish Conservative leader, have backed the calls.
The Representation of the People Act also abolished nearly all property qualifications for men.
As a founder member of the Women's Social and Political Union (WSPU), Pankhurst was sentenced to repeated stretches in prison as a result of her militant activity.
"Voting was a value judgment, not an intrinsic right", she wrote in Tuesday's the Daily Telegraph. "That inequality is one reason why I support calls by family members to offer a posthumous pardon to those suffragettes charged with righting that wrong".
From separation in 1922, the Irish Free State gave equal voting rights to men and women.
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A coarsening of politics by "bitterness and aggression" online has disproportionately led to the targeting of political candidates who are female, black, minority ethnic or LGBT, the Prime Minister will say.
She added: "I sometimes wish I could just speak to them for a moment and say "you will win, you will prevail". "That for some it is becoming harder to disagree, without also demeaning opposing viewpoints in the process".
Ministers will also launch a Law Commission review into whether the law is fit for objective in ensuring what is illegal offline is also illegal online.
Mrs May will later launch a year-long Vote 100 programme of events to celebrate a century of female suffrage.
A London rally in 1908 brought hundreds of thousands of women to support the Suffragettes and saw the largest number of people gathered in Hyde Park for a political objective, according to the Museum of London.
Meanwhile, Royal Mail has announced it will be issuing a set of Special Stamps to mark the centenary of the Representation of the People Act.
Three other pieces of legislation that gave women the vote on the same terms as men, allowed women to be MPs and allowed women to sit in the House of Lords as life peers, will also be displayed.
Theresa May will use the centenary of the suffragette movement to warn that the growing level of abuse and intimidation on social media is deterring people, particularly women, from public life.